The packaging and assembly of a waferscale system on chip

• Main Authors: Veen, C. van, Samber, M. de, Bergveld, H., Ackerveken, A., Slob, C., Manessis, D., Ostmann, A., Whitmore, M.
• Format: Conference Object
• Language: English
• Published: 2005
• Subjects: 621; Blue whale
• Online Access: https://publica.fraunhofer.de/handle/publica/348359

S.184-189 At the IMAPS Europe 2004 in Prague a session was held on the Blue Whale project. At that time theproject was well underway, with one year to go. At IMAPS Brugge we want to present the projectresults from the Blue Whale project in terms of what it has given us in terms of miniaturization,electrical performance and packaging reliability. As part of the Blue Whale project a miniaturised "System-on-Chip" system, consisting of an analogueradio and a digital microprocessor, has been packaged for the wireless communication market. Thispackaging is done using wafer level Shellcase packaging technology to achieve "true die size"packaging, and therewith the highest miniaturisation is achieved. Improvements on "standard"Shellcase design rules were required to accommodate the 48 IOs, leading to a 400 µm ball pitch,whereas at the same time the peripheral pitch of the Shellcase package had to be reduced to 225 µm.For cross-talk reduction between the microprocessor and the radio, the Si from the substrate has beenthinned over the whole wafer. Additionally, trenches, with partly total removal of the Si, have beenmade between the radio and microprocessor for a more complete decoupling.In the presentation the result of the packaging activity, specifically the electrical comparison with thepackaging of the same, but unthinned and untrenched die in an LQFP, will be presented. It is for thefirst time that such comparison for the sake of cross talk reduction is performed.